Background:　The　sensitivity　of　5,5　＇-dithiobis-(2-nitrobenzoic　acid)　(DTNB)　method　may　not　be　enough　to　detect　low　concentration　glutathione　(GSH),　especially　in　complex　samples,　which　limits　its　application　in　some　biologic　scenarios.　Fluorescent　carbon　quantum　dots　(CQDs)　have　garnered　significant　interest　in　bioanalytical　applications　due　to　their　unique　properties,　particularly　the　sensitivity　in　the　detection　of　complex　samples.　Results:　In　this　work,　carbon　quantum　dots　(TOCDs)　were　prepared　via　pyrolysis　method　of　D-threonine　and　o-phenylenediamine.　Considering　advantages　of　selectivity　of　DTNB　and　sensitivity　of　TOCDs,　a　simple,　fast　and　sensitive　fluorescent　sensor　based　on　TOCDs　and　DTNB　was　fabricated　for　selective　detection　of　GSH.　In　the　presence　of　GSH　in　the　mixture　of　TOCDs　and　DTNB,　-SH　of　GSH　can　interact　with　DTNB　and　subsequently　affording　5-thio-2-nitrobenzoate　(TNB),　which　can　strongly　absorb　excitation　light　of　TOCDs　and　lead　to　fluo-rescence　quenching　of　TOCDs.　As　a　consequence,　quantitative　screening　of　GSH　can　be　achieved　through　the　fluorescence　intensity　of　TOCDs　was　decreased　after　the　addition　of　GSH　in　the　system　of　TOCDs　and　DTNB.　Under　optimized　conditions,　good　linear　relationships　in　the　range　of　2.5-40　nM,　40-150　nM　and　150-1000　nM　for　GSH.　TOCDs　can　effectively　detect　GSH　with　a　limit　of　detection　(LOD)　1.5408　nM.　The　feasibility　of　the　TOCDs　probe　was　verified　through　non-invasive　detection　of　reduced　glutathione　(GSH)　in　bacteria　and　cells.　The　fluorescence　of　TOCDs　in　different　living　bacteria/cells　were　yellow　fluorescence,　while　the　fluorescence　could　be　ignored　after　joining　GSH　and　DTNB.　The　mechanism　about　quench　phenomenon　of　the　fluorescence　intensity　between　TOCDs　and　DTNB/GSH　was　the　inner-filter　effect.　These　results　demonstrated　that　the　presented　fluorescent　sensor　could　be　a　promising　sensing　platform　for　GSH　analysis.　Significance:　This　sensing　strategy　could　be　expanded　to　more　access　to　the　GSH-induced　acute　toxicity　and　disease.　The　yellow　fluorescence　carbon　quantum　dots　demonstrated　its　potential　application　on　GSH　detection　in　bacteria　and　cells.